Build: Fix three new warnings in HLSL code.
diff --git a/hlsl/hlslGrammar.cpp b/hlsl/hlslGrammar.cpp
index 5381885..c149b1c 100755
--- a/hlsl/hlslGrammar.cpp
+++ b/hlsl/hlslGrammar.cpp
@@ -211,7 +211,7 @@
 // sampler_declaration_dx9
 //    : SAMPLER identifier EQUAL sampler_type sampler_state
 //
-bool HlslGrammar::acceptSamplerDeclarationDX9(TType& type)
+bool HlslGrammar::acceptSamplerDeclarationDX9(TType& /*type*/)
 {
     if (! acceptTokenClass(EHTokSampler))
         return false;